Such a laminate is known from U.S. Pat. No. 5,180,190. In this patent a container for the transportation of fluids is described. The wall of the container has a laminate structure, containing a first layer, basically forming the wall of the container. On top of the first layer a second layer is attached containing a fabric of high tenacity yarns and a matrix. The matrix adheres to the yarns and to the first layer.
Object of the second layer is to improve the damage resistance of the container.
The known laminate has the disadvantage of having an unsatisfactory damage resistance. Especially if the laminate is hit with a large blunt object the damage is severe, due to tearing of the fabric over large distances, also referred to as cascade damage. Damaging of this kind often occurs. For example it may occur that while handling the container, the wall of the container is hit by a forklift truck. By hitting the container wall the fork breaks the single yarns sequentially, both in the warp and weft direction and in the subsequent layers if present.
Object of the invention is to provide a laminate having improved damage resistance.
Surprisingly this object is obtained by providing a laminate containing a first layer and a second layer attached to the first layer said second layer comprising high tenacity yarns having a tenacity of at least 0.5 GPa, wherein the high tenacity yarns are positioned in a grid structure.
The laminate according to the invention is very well damage resistant. The laminate according to the invention is especially resistant against cascade damage.
A further advantage of the laminate according to the invention is that it has a low weight, so that it is very suitable for use in the construction of mobile, light weight constructions, for example air freight containers.
It was further surprisingly found that the laminate of the invention when compared with known laminates, it has a higher energy absorption when impacted by fast moving objects, i.e. objects moving with a velocity of higher than 40 m/s which are due to, for example, an explosion or blast occurring in the vicinity of the laminate.
Moreover the laminate may be produced in various designs, to fulfill all kind of demands, determined by its intended use.